Refrigerating system



March 8, 1938. H, WOODARD 2 ,110,689

REFRIGERATING SYSTEM Filed March 29. 1935 I INVENTOR.

6 801 elfl/lfbodand Y BY E '2- HIS ATTORNEY I Patented Mar. s; 1938 2,110,689 REFRIGERATING'SYSTEM George H. Woodard, Phillipsburg, N. 3., assignor to Ingersoll-Rand Company, Jersey City, N. J., a corporation of New Jersey Application March 29,1935, Serial No. 13,641

10 Claims.

' This invention relates to an improved refrigerating system, especially that part of the system wherein the refrigerant is treated to put it into condition for producing the desired refrigcrating effect.

In refrigerating means of the water-vapor type a liquid refrigerant is cooled in a closed vessel called an evaporator and then removed therefrom to the placewhere it is used for the intended purpose. In prior constructions of this kind, the refrigerant is generally admitted to the evaporator near the top and taken out through a delivery conduit connected to the bottom. The conduit leads to a force pump which is at a lower level than the evaporator, so that the liquid entore the pump with the required static head thereon. Such a disposition of parts often makes the apparatus too high to permit easy installatire installation when set up in operative pos tion, is materially'reduced in height. I

A. further object of this invention is to provide a system wherein the evaporator and the pump for removing the liquid contents of the evaporator are so related that the pump can be.

placed at substantially the same level as the evaporator, thus reducing the vertical room that would otherwise be needed, while the refrigerant can still enter the pump at sufficient statlc'head to enable the pump to work at its full efliciency. Another object of the invention is to provide an evaporator adapted to facilitate the delivery of the refrigerant therefrom, and so arranged that, when the evaporator or part thereof is to be rendered non-operating, it can be readily 40 sealed with respect to the delivery conduit without the use of valves or other controlling means in the latter. Hence, with an evaporator containing several chambers, one or moreof same can easily be cut out at times when the system is to I w run at part load. Under such circumtsances whenever refrigerating action in a chamber is suspended the discharge of the refrigerant therefrom is automatically stopped.

An additional object of the invention is to prom vide an evaporator to which the refrigerant is admitted under some pressure 'at sucha point that the inflow thereof assists the outflow by positively impelling the refrigerant toward the out let of the evaporator where it enters the delivery :35 pipe for removing same.

The foregoing and other objects and advantages 'of this invention are fully and clearly set forth in the ensuing description, and while a preferred form of the-invention is illustrated cc herein on the accompanying drawing, I reserve the right to make changes in various Ways without departing from the principle of the invention or exceeding the scope and spirit of the appended claims.

0n the drawing Figure 1 shows in outline a regrigerating system according to this invention, partly in section on the line |-l of Figure 2, and

Figure 2 is a section on the line 2--2 of Figure 1 showing an evaporator with several chambers, all or part of which may be operated at one time. f

The same numerals identify the same part throughout. 7

. The numeral l indicates an evaporator in the form of a closed vessel mounted upon a suitable support or foundation 2. Through a pipe 3, a

refrigerant lowered in temperature is removed 7 by way of an outlet 6 and delivered to a conduit 5 through which it passes to a cooling coil 6. This cooling coil will be in a space or compartment where the cooling edect is desired. In practice heat will be absorbed by the refrigerant in the coil 6. The refrigerant is thus warmed before it again reaches the conduit 3 and is conducted back to the evaporator to be cooled once more. In the top of the evaporator is an opening l leading to the inlet 8 of a suitable evacuator (not shown) by which the water vapor that is formed in the evaporator l is extracted and discharged into a condenser to be liquefied.

The delivery conduit 5 is coupled to the evaporator I through a pump 9 which is driven by a motor Hi. In the usual construction the return height, the need for saving space can be quite pronounced. I therefore lead the return water pipe 3 'into the interior of the evaporator at a. much lower point so that the water can be introduced near the bottom, and the pump 9 is mounted at the sarne level as the evaporator l The evaporator is provided with an. inclined surface shown at it in Figure 1 which slopes upward from a point near where the return water is admitted, toward the outlet. .The inclined surface, which may be the bottom of the evaporator, is connected with the top of a vertical wall or partition shown at 42 and cooperates therewith and with the walls of the evaporator I to define an outlet well or recess I 3 in one end' of the evaporator against the outlet 4 and a second recess in a horizontally distant end of the evaporator adjacent the point where the pipe 3 enters the evaporator. The outlet 5 is located at or near the bottom of the well I3 in the side of the evaporator I. Above the surface I I is a cover or screen. I4 which forms with said surface an upwardly inclined channel or throat through which the refrigerant passes on its way to the well I3. At the lowest point of the surface II the return water issues through one or more nozzles I5. As shown in the drawing the refrigerant is forced through pipe 5, coil 6 and conduit 3 under some pressure and when it enters the evaporator it is expelled from. the nozzle or nozzles I5 with some velocity. The energy of the jet issuing from each nozzle I5 agitates the water and impels it against the force of gravity through the ascending guiding channel between surface II and cover I4. During this movement part of the refrigerant is vaporized, the vapor being removed through the opening I. By the time the water reaches the well I3 it is lowered in temperature by several degrees and is in the condition required. Therefore the outlet 4 does not have to be in the bottom of the evaporator but can even be a short distance above the bottom as indicated in Figure 1, and the height of the evaporator as well as the height of the whole apparatus, except for the coil 6 which may. be at any selected point is much reduced. In fact the total height is no greater than that of the evaporator alone. The energy of the incoming water thus not only divides the refrigerant into small particles but also impels the water up along the false-bottom into the well,- from which it is delivered into the conduit 5. The screen I4 is, of course, spaced from the side where the pipe 3 enters and from the top of the evaporator, and all the water which is agitated is between this screen and the surface. The water vapor which is formed in the operation can flow around the upper and lower edges of the screen or cover for the channel on its way to the opening I. A baffie plate may be disposed beneath the outlet opening I if desired.

Figure 2 shows the evaporator with a partition I6 dividing it into two compartments which appear in end view in Figure 2. Each compartment will be provided with an inclined surface I I joined to a tranverse partition I2 at one end, the surface and partition extending from one side to the other of each compartment. The admission or supply pipe 3 is provided with branches I! one leading to each-compartment at the end remote from the delivery well or reservoir I3 therein and each of these branches may carry a casing I8 containing a valve which can be manipulated by an outside knob or head I9. Eachbranjch I'I leads to a length of piping 20 inside the compartment associated therewith and at the bottom of each piece of piping is a transverse header 2| carrying two or more nozzles I5 in line with the channel between the surface I I and the screen I4. The outlet openings 4 of the chambers of this evaporator are .coupled to branch conduits 22 connected to a short pipe 23 which leads to the inlet port of the pump 9. In Figure 2 the pump 9 is indicated in broken lines to show its posi- Inpractice this system can be operated with all or less than all the chambers working. When all the chambers are working and the system is thus running at full load, the incoming water discharged from the nozzles I5 collects to the level shown in Figure l at the bottom of the evaporator, and the jets created by the nozzles I5 force the water up along the inclined surface II and over the upper end of same so that it can fill the receptacles I3. As the water is urged upward along the surface I I itis agitated by these jets so that the vaporization of part is assisted. From the Wells I3 the cooled water passes to the pump and is transmitted by way of the conduit 5 to the coil 6. When operation of part load is desired, one of the chambers, or when there is a larger number, more than one chamber can be cut out by shutting the valve in the branch I! of the chamber or chambers not needed. When centrifugal evacuato-rs are connected to the outlets I, the evacuator for an inactive chamber may continue to rotate but then does no useful work, and when steam evacuators are employed, the'steam for the evacuator of any inactive chamber is cut off.

operating, without requiring any valves in the branches 22 leading from the outlets 4 to the pump 9. For example, when a chamber is working the refrigerant, after being cooled, will fill the well I3 to the depth shown in Figure l or at the left of Figure 2. But when any chamber is put out of action by closing the valve attached to the knob I9 thereof in the inlet branch 11 and stopping the evacuator the vacuum in that chamber will decrease and the pressure therein will rise somewhat. This is'true when the inlet 8 leads to a steam jet ejector which is in open communitil cation with a condenser. In such a case, whenever the steam jet is stopped, the condenser pressure will prevail in the chamber that is being cut out. This pressure will be higher than the vacuum in that chamber and it will force down the level of the liquid in'the well I3 to a point shown at the right of Figure 2. By making the partition I2 high enough the level of the liquid will then still be above the outlet 4 and enough liquid will be trapped in this well to seal it, while the other chamber or chambers continue working. Hence no valves in the branches 22 between the outlets 4 and the pump are required. Each well thus constitutes a simple and effective means to facilitate the delivery of the refrigerant from the evaporator and control the outflow. But valves, of course, can be included if preferred. When centrifugal evacuators are used, the water is likewise trapped in the well of an inactive chamber, but the level thereof may not sink so much.

Thus the invention is well adapted to diminish the over-all height of the evaporator I and its auxiliary devices and of the evaporator itself so as to facilitate the installation of the system in places where only a restricted amount of .space is available above the support 2. The pump is far enough below the level of the refrigerantln the well I3 to have all the static head it needs and yet it is no lower than the evaporator itself. The location of the nozzles I5 near the bottom of the evaporator enables the depth of the evapentire height of evaporator, pump and evacuating means (not shown) above the evacuator is actually less than the aggregate height of evaporator and evacuator means in systemscomprising ordinary evaporators with the pump under same. This result is obtained chiefly by mounting the nozzles I5 at the lower part of the evaporator, and causing the water to ascend the inclined surface H until it reaches the wells l3 system comprising an evaporator, a spray nozzle disposed to discharge a liquid refrigerant into the evaporator, means forming a delivery well to receive said refrigerant at a point above said nozzle, means in the evaporator forming an upwardly inclined bottom between the delivery well and the nozzle, and a member overlying said bottom forming therewith a channel through which the liquid refrigerant is forced by the jet from said nozzle to said well.

3. In a refrigerating system, an evaporator having a plurality of chambers, means for injecting a refrigerant into each of the chambers, the chambers each having an outlet, means forming a delivery well within each chamber adjacent each outlet, the entrance of said wells being above said injection means, and means forming an inclined channel within each chamber through which refrigerant from said injection means is impelled into said wells by theforce of the injected refrigerant, the ends of the channels communicating with the chambers to enable vapor to pass from the liquid into the chambers before the liquid enters and after the liquid leaves the channels.

4. In a refrigerating system, the combination of an evaporator having an outlet above the bottom, a nozzle to inject a liquid refrigerant into the evaporator, and means within the evaporator forming an upwardly inclined channel through which the said refrigerant is impelled by the energy of the discharge of said nozzle to a point above said outlet, each end of the channel opening into the evaporator to enable vapor to escape from the liquid before the liquid enters and after the liquid leaves the channel.

5. An evaporator for cooling refrigerant by partial vaporization, a refrigerant inlet and outlet for the evaporator, refrigerant guide means open within the evaporator and interposed between said inlet and outlet to guide refrigerant, while it is being vaporized and cooled, from said inlet to a'point above said outlet, said means providing space in the evaporator for effective vaporization of the refrigerant, and means associated with said inlet and said guide means to impart kinetic energy to the entering refrigerant and impel the same over said guide means to said point above the outlet thereby to provide static head on the outlet.

6. In a refrigerating system, an evaporator for cooling liquid refrigerant by partial vaporization, a nozzle injecting the refrigerant into the evaporator below the normal level of the reirigerant contained therein, a guide conduit in the evaporator for refrigerant projected by the nozzle and extending upwardly to a level higher than said normal level of -refrigerant in the evaporator, and an outlet for the refrigerant at such higher level, said nozzle being adapted to agitate the refrigerant in the evaporator to facilitate vaporization thereof, said conduit being open in the evaporator adjacent the nozzle and at said higher level for effecting vaporization of the refrigerant both at its entrance to the evaporator and after the refrigerant is raised to the higher level.

'7. In a refrigerating system, an evaporator for refrigerant having two or more chambers, each chamber having a refrigerant outlet, a nozzle in each chamber to inject refrigerant thereinto,

means within each chamber forming an upwardly inclined channel therein through which refrigerant isimpelled by the energy of the discharge of said nozzles to points above said outlets, each of said channels opening at each end thereof into its chamber to enable vapor to escape from the refrigerant before the liquid enters and after the liquid leaves the channels, and means joining said outlets in parallel whereby when one of said chambers is inoperative the refrigerant in said joining means cooperates with the liquid at the outlet of said inoperative chamber to seal the latter from the operative chambers.

8.. An evaporator tank having walls defining a chamber, means in the chamber cooperating with said walls to define a recess in one end of the chamber and another recess in a horizontally distant end of the chamber, an inlet for liquid to the evaporator and delivering to the first said recess, an outlet for liquid from the evaporator from the second said recess, said means including a surface extending from one recess to the other, and means to transfer liquid from the first said recess over said surface to the second said recess.

9. An evaporator tank having walls defining a chamber, means in the chamber cooperating with said walls .to define a recess in one end of the chamber and another recess in a horizontally distant end of the chamber, an inlet for liquid to the evaporator and delivering into the bottom of the first said recess, an outlet for liquid for the evaporator from the bottom of the second said recess, said means including a surface extending upwardly from the first recess to the top of the second recess, and means for injecting the liquid into the first said recess below the normal level of the liquid therein to impart force to the liquid in the recess for impelling such liquid over said surface to the second said recess.

10. In a refrigerating system, an evaporator, means forming an inlet well in one end of the evaporator and an outlet well in the other end, said means including an inclined surface joining said wells, a vapor outlet for said evaporator, a cover over said surface forming a. passageway therebetween and shielding said surface from said vapor outlet, and means for injecting refrigerant under pressure into said inlet well to agitate the refrigerant therein to facilitate the vaporization of a part of said refrigerant and to impel the unvaporized refrigerant by the force of the injected refrigerant through said passageway into said outlet well.

GEURGE HI, WtiQDA-RD. 

